When Supernatural sticks to doing original stories, there are few shows that can match its creativity and execution. Ten seasons have given this show a rich mythology, and it’s immensely rewarding to see characters and settings from seasons past used in exciting new ways. It’s also fun to see material expanded in ways that feel organic and not like they’re simply plot contrivances. Such was the case tonight with the Werther Box and the Men of Letters backstory that accompanied it.

The callbacks we got in this episode were of course Benny and Purgatory, two elements with deep ties to Dean’s growth as a character in Season 8. Benny could be grating at times as a character but his effect on Dean was illuminating. Their brotherly bond was forged in the heat of battle, and Dean appreciated the simplicity – the purity – of fighting to survive. Benny was right to question if Purgatory was Dean’s happy place, since the eldest Winchester seems right at home among the monsters who roam the washed-out landscape. It was no mistake the Werther Box spell brought him back to that place and summoned Benny from deep in his subconscious.

This episode had a number of creepy elements that made it feel like vintage Supernatural. The cold open was both retro and utterly disturbing. Though I initially questioned why young Susie felt compelled to smash down a wall in her basement, I quickly let go of that gripe once the spell escaped the box and viciously killed off her family members. There were also far too many wrist and throat slits in this episode. As someone who gets squeamish just hearing the word “slit,” I was nearly gagging at the sight of Rowena working the blood down Sam’s arm. Enough slits, writing team.

There were some other nice references to earlier episodes in this hour. Bringing back Magnus, the Man of Letters formerly known as Cuthbert Sinclair, for the first time since Dean cut his head off in Season 9’s “Blade Runners” was a nice touch. I enjoyed seeing the moment when he apparently got booted from the Men of Letters. A more indirect reference came in the parallels between Dean’s trip to Purgatory and Sam’s near-death experience in the Season 9 premiere, “I Think I’m Gonna Like It Here.” Sam and Dean both grappled with the possibility of letting go in these instances and it comes as no surprise that Sam was ready to let go, whereas Dean wholeheartedly refused. Some of that is due to the Mark’s grip on Dean’s mortality, but we all know Dean is going to hang on for as long as he can in order to keep fighting and keeping his brother safe. It’s a strength and a weakness for him.

Two notes on Sam before we wrap up. First off, good on Susie’s “ghost” for letting Sam have it following her death. Sam royally screwed up and got Susie killed after she’d kept the box at bay for decades. Her blood was on Sam’s hands, and I’m glad she ripped him a new one for it. Secondly, Sam is an idiot for trusting Rowena. We know this, and it’s certain that Dean and Castiel would think the same thing. Even Crowley wouldn’t trust his mother to decode a dangerous book of spells. (Side note: does that book seriously not contain a spell to break someone out of chains?) Sam is playing with fire, and this season is going to end with everyone getting burned, mark my words.